Transportation of cargo by airplane requires lightweight containers to reduce cargo weight. The containers are generally made of a lightweight metal such as aluminum which is easily damaged if improperly handled. This type of container can be sealed when loaded which minimizes theft during transfer and storage. The sealed container also reduces the number of containers that have to be handled by the shippers. Since the cost of the containers is high and the cost of repairing a damaged container approaches the cost of the new container, it has become extremely important that exposure to damage be minimized.
Most shippers and consignees do not have transporting equipment to move the lightweight containers without damage. The containers are generally transported by fork lift trucks. Most damage occurs when a container is picked up by a fork lift truck. In this regard, roller type pallets have been used to protect the bottom of the container. Since the palletized containers are transported by fork lift truck and highway trucks, any bump or jolt in the movement of the truck results in the indentation of the rollers of the pallet into the bottom of the container producing a washboard configuration. Once indented it becomes difficult to move the containers on roller type conveyor systems. The containers are also designed to closely fit within the air craft and it is, therefore, important that they are properly aligned on the air craft conveyor system so that they do not come in contact with the walls of the aircraft or the adjacent containers when they are moved into and out of the aircraft.